Online service providers facilitate access to information and services by providing interactive User Interfaces (UIs) that help users navigate to desired resources. For example, in the case of a system for communicating using instant messages (IMs), a UI allows an IM sender to invoke actions, such as establishing a communications link, through the selection of screen objects such as icons, windows, and drop-down menus. The design of a UI has a significant impact on an IM sender's online experience. In particular, the icons, the windows, and the menus of a UI may be arranged to enable an IM sender to locate information and services quickly and easily.